Korean shamanism, also known as musok (Korean: 무속; Hanja: 巫俗) or Mu-ism (무교; 巫敎; Mugyo), is a religion from Korea. Scholars of religion classify it as a folk religion and sometimes regard it as one facet of a broader Korean vernacular religion distinct from Buddhism, Daoism, and Confucianism. There is no central authority in control of musok, with much diversity of belief and practice evident among practitioners.
A polytheistic religion, musok revolves around deities and ancestral spirits. Central to the tradition are ritual specialists, the majority of them female, called mudang (무당; 巫堂) or mu (무; 巫). In English they have sometimes been called "shamans", although the accuracy of this term is debated among anthropologists. The mudang serve as mediators between paying clients and the supernatural world, employing divination to determine the cause of their clients' misfortune. They also perform kut rituals, during which they offer food and drink to the gods and spirits or entertain them with storytelling, song, and dance. Kut may take place in a private home or in a kuttang shrine, often located on a mountain. The mudang divide into regional sub-types, the largest being the mansin or kangsin-mu, historically dominant in Korea's northern regions, whose rituals involve them being personally possessed by deities or ancestral spirits. Another type is the sesŭp-mu of eastern and southern regions, whose rituals entail spirit mediumship but not possession.
Elements of the musok tradition may derive from prehistory. During the Joseon period, Confucian elites suppressed the mudang with taxation and legal restrictions, deeming their rites to be improper. From the late 19th century, modernisers – many of whom were Christian – characterised musok as misin (superstition) and supported its suppression. During the Japanese occupation of the early 20th century, nationalistically oriented folklorists began promoting the idea that musok represented Korea's ancient religion and a manifestation of its national culture; an idea later heavily promoted by mudang themselves. In the mid-20th century, persecution of mudang continued under the Marxist government of North Korea and through the New Community Movement in South Korea. More positive appraisal of the mudang occurred in South Korea from the late 1970s onward, especially as practitioners were associated with the minjung pro-democracy movement and came to be regarded as a source of Korean cultural identity.
Musok is primarily found in South Korea, where there are around 200,000 mudang, although practitioners are also found abroad. While Korean attitudes to religion have historically been fairly inclusive, allowing for syncretism between musok and Buddhism, the mudang have nevertheless long been marginalised. Disapproval of mudang, often regarded as charlatans, remains widespread in South Korea, especially among Christians. Musok has also influenced some Korean new religions, such as Cheondoism and Jeungsanism.